The `logging` part of `common` was exported in `common/index.ts` and
could be imported by importing `common`. I don't think this makes a lot
of sense, so I removed it.
The `common/logging/index.ts` also contained exports of the
`common/logging/vscode` directory, which means that importing
`common/logging` automatically brings in the `vscode` module. This
removes that export, so now there are two separate imports needed for
importing the common part and the `vscode` specific part. This should
make it easier to keep them separate and be more explicit about what
you're importing.
